Central and peripheral nerve injuries can lead to permanent paralysis and organ dysfunction. In recent years, many cell and exosome implantation techniques have been developed in an attempt to restore function after nerve injury with promising but generally unsatisfactory clinical results. Clinical outcome may be enhanced by bio-scaffolds specifically fabricated to provide the appropriate three-dimensional (3D) conduit, growth-permissive substrate, and trophic factor support required for cell survival and regeneration. In rodents, these scaffolds have been shown to promote axonal regrowth and restore limb motor function following experimental spinal cord or sciatic nerve injury. Combining the appropriate cell/exosome and scaffold type may thus achieve tissue repair and regeneration with safety and efficacy sufficient for routine clinical application. In this review, we describe the efficacies of bio-scaffolds composed of various natural polysaccharides (alginate, chitin, chitosan, and hyaluronic acid), protein polymers (gelatin, collagen, silk fibroin, fibrin, and keratin), and self-assembling peptides for repair of nerve injury. In addition, we review the capacities of these constructs for supporting in vitro cell-adhesion, mechano-transduction, proliferation, and differentiation as well as the in vivo properties critical for a successful clinical outcome, including controlled degradation and re-absorption. Finally, we describe recent advances in 3D bio-printing for nerve regeneration.

Klebsiella pneumoniae (KP) with the hypermucoviscosity (HV) phenotype has abundant capsular polysaccharides (CPS) and usually causes an invasive syndrome. Sialic acid (Sia), a component of CPS in K...

Neonatal monocytes express lower miR-125b, a negative regulator of TNF-α expression, resulting in higher TNF-α responses after LPS stimulation. Neonates, although deficient in cell immunity, frequently reveal sepsis with augmented proinflammatory reactions. Here, we found that neonatal monocytes produced significantly higher TNF-α mRNA and protein than adult monocytes. Assessment of the transcriptional factor found no significant difference of NF-κB p65 level between neonatal and adult monocytes. Addition of Act D to access the half-life of TNF-α mRNA revealed no significant difference of the LPS-induced TNF-α mRNA half-life between them, whereas CHX increased neonatal TNF-α mRNA significantly. This suggests that a post-transcriptional mechanism involves the augmentation of TNF-α production by neonatal monocytes. To examine whether miRNA was involved in the post-transcriptional regulation, differential displays of miRNA array between neonatal and adult MNCs were performed, along with the discovery of hsa-miR-103, hsa-miR-125b, hsa-miR-130a, hsa-miR-454-3p, and hsa-miR-542-3p, which were greater than a twofold decrease or increase after LPS treatment for 4 h. The functional validation identified that miR-125b decreased significantly in association with higher TNF-α expression by neonatal monocytes after LPS stimulation. Transfection of the miR-125b precursor into neonatal monocytes significantly repressed the TNF-α mRNA and protein expression, suggesting that miR-125b negatively regulates TNF-α expression in neonatal monocytes. Modulation of miRNA expression may be used to regulate TNF-α production in newborns with altered proinflammatory reactions.

Objective: Kawasaki disease (KD) is characterized by systemic vasculitis, and it is the most common acquired heart disease in children. However, the etiology and immunopathogenesis of KD are still unclear. A genome‐wide association study (GWAS) identified polymorphisms in CD40, BLK, and FCGR2A as the susceptibility genes for KD. No epigenetic array studies of KD have previously been published. This study was undertaken to investigate differences in DNA methylation in patients with KD as compared to controls.Methods: The HumanMethylation27 BeadChip (Illumina) was used to survey the differences in DNA methylation between KD patients and controls. DNA methylation array validation was performed in a separate cohort by pyrosequencing assay and reporter gene assays. Messenger RNA (mRNA) expression was determined, and the association of methylation with response to intravenous immunoglobulin (IVIG) treatment was analyzed.Results: HumanMethylation27 BeadChip assay showed a 15% difference in methylation of 10 genes between KD patients and controls. The FCGR2A cg24422489 group, which was recently reported to be associated with KD susceptibility in a GWAS, had significant hypomethylation of 15.54% less in the KD group than in the control group. Validation of FCGR2A methylation in another cohort also showed significant hypomethylation in the KD group (5 of 5 CpG sites [P < 0.01]; n = 43 in the KD group and n = 55 in the control group). KD patients with IVIG resistance showed hypomethylation of 5 CpG sites (P < 0.05). FCGR2A mRNA expression was significantly increased in patients in the acute stage of KD compared to controls. Reporter gene assays indicated that the CpG sites of the FCGR2A promoter region were sufficient to modulate gene expression.Conclusion: This is the first study to examine the DNA methylation array in KD and identify a role of hypomethylation of FCGR2A in susceptibility to KD and IVIG resistance.